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Basic Info.
Product Description
0.312 0.5 mandrel size 0.767 OD 302 stainless steel torsion spring
DOFO spring is a leading manufacturer of single & double torsion springs which can be found in clothespins, window shades & more.
#1 ATTN: Read This Before BuyingA. Due to the internet and computer display solutions. The actual products may differ from
the pictures. Please contact our salesmen for further assistance.
B. All the extension springs, compression springs, torsion springs, wire forms can be made in customized demands.
C. We appreciate Drawing-Guide Production, Please send us a spring drawing as possible as you can when you inquiry.
D. We appreciate your inquiries and you are welcome all the time!
For a better understanding of your demand, please learn the basics of torsion spring manufacturing.
#2 Working Drawing of a torsion spring
#3 Different Shapes of Helical Torsion Springs
There are generally two common types of torsion springs: single and double coil torsion springs. Double torsion springs are two single torsion springs connected. They work together to double the torque that a single spring would produce.
#4 Available Coating Method
Due to the government's environment policy, all the coating materials are prior to RoHS standards. Please take RoHS standard coating as possible as you can. Below is a table for reference, you can simply learn the cost of each coating method.
| Coating Method | Cost | Does it Meet the RoHS requirement? | Remark |
| Unplated | None | Yes | |
| Anti Rust Oil | Lowest | Yes | |
| Black Oxide/Oxide | Lower | Yes | |
| Normal Zinc coating | normal | No | |
| Trivalent Zinc coating | High | Yes | Normally 8~10μ thickness, 48 hours without white rust |
| Nickel Plated | normal | Yes | |
| Electrophoresis | Higher | Yes | |
| Painting | Very High | Yes | require a longer delivery time |
| Stainless steel Washing | normal | Yes | |
| Stainless Steel Electro-polish | Highest | Yes | This coating cost more than the others |
Q: Which kind of materials are available? Do they meet RoHS certification?
A: DoFo Spring is able to manufacture different spring types of compression springs, extension springs, torsion springs, wire forms with a large range of High-Grade Spring Steel - Carbon steel - Stainless steel - Music Wire, all comply to the RoHS standard. The wire diameter is available from 0.001 inches to 0.075 inches, which can meet the requirement of different applications.
Q: Do you support orders in small quantity or do you only accept large runs?
A: DoFo Spring manufactures large quantity springs, small quantity springs based on your demand. We will work with you to choose the most effective solution.
Q: Does DOFO spring offer DESIGN service OR initial ASSISTANCE ON SPRINGS?
A: Our engineers could give initial assistance on the design and advise to lower the production cost. Our engineer has years of experience in spring design. We could provide drawing format in CAD, 3D, and 2D design layout as well as prototype development.
Q: What is the typical lead time for custom springs?
A: The lead time varies in custom springs. For compression springs, extension springs, torsion springs, wire forms in our mold range, we are able to deliver within 25 days. However, for some complex shapes of springs, the delivery time would be around 30~40 days.
Q: Do you charge custom spring samples?
A: We make the custom springs sample charge as a subscription of formal order. In other words, the sample charge could be refunded when we receive the order. However, if your sample requires an additional mold, we will charge it.
Q: If we order large quantity springs, will you house the springs, wire forms, and ship to us based on a required basis?
A: Our warehouse provides specific stock service for long term business. You can make your shipment schedule on an annual, monthly basis. We will ship on a specific schedule.
Q: What payment term do we accept for spring orders?
A: We could accept payment terms based on T/T, L/C at sight, DP, Westunion.
If any question, please contact us directly.
